The present invention is based on a motor-driven compass saw machine.
A hand-guided, motor-driven compass saw machine with an oscillation mechanism is known from DE 198 06 05 675. This oscillation mechanism deflects the saw blade, which is secured in a lifter rod, in the cutting direction by means of a roller lever. This deflection in the cutting direction, which is referred to as an oscillation stroke, results in a faster forward progress of the saw. The oscillation stroke can be adjusted by means of adjusting knob; discrete adjustments of the deflection can only be selected in steps. A stop that the roller lever strikes against when it is deflected limits the maximum deflection, which is different in each fixed step.
The greater the oscillation is, the faster the cut progresses. But the cutting quality suffers as a result of this because it produces tear-outs at the edges of the cut as well as rough cut surfaces. In addition, cutting control decreases as the cutting speed increases. But switching between the individual oscillation stages by rotating the stop is complicated, as a result of which it is regularly not carried out during sawing. But this really should be done since requirements for cutting processes change frequently. Thus, for straight parts, a rapid cutting speed is preferable, but in tricky, curved passages, or when carefully starting a cut, a slow cutting speed with a higher cutting quality is preferable. Both of the above-mentioned extremes can alternate continuously, thus requiring the user to constantly adjust the oscillation.